How would you model this led strip?
Here’s one way to do it:

Start with a profile mesh for the strip:


Add a Screw modifier with 0° for the angle and a suitable number of iterations:


Add an Archemedian Spiral curve with the appropriate parameters to get the rough shape, and in the curve properties, set the Twist Method to Z-Up.


Add a Curve modifier to the strip object with the Deform Axis set to Z:



The trickiest parts of this seem to be getting the normals correct on the extruded mesh produced by the Screw modifier and getting the twist right on the curve. Checking the Calculate Order box in the Screw modifier options seemed to help with the normals, and using the Z-Up twist method for the curve produced the right twisting.